Blackboard



C. H. KRAFT July 5, 1932.

BLAGKBOARD Filed Deo. 19, 1930 J ATTORNEY-5.

Patented July 5, 1932 UNITED STATES CHARLES H. KRAFT, F KANSAS CITY, MISSOURI y '.BLACKBOARD Appncation mea December 1e, 1930. serai No. 503,406.

This invention relates to blackboards and particularly to swinging blackboards having a plurality of panels or leaves mounted on a common axis in such a manner that each panel is movable to present both of its sides to the operator.

The principal obj ect of this invention is to provide a blackboard comprising a panel supported at one of its ends by a hingedly mounted frame and means carried by said frame adjustable to raise or lower the outer end of the panel so that all the panels of a set, mounted for oscillation on a common axis, may be easily and quickly adjusted to register in horizontal alinement.

A further object of this invention is to provide a blackboard having a plurality of vertically disposed panels carried by frames mounted for oscillation on a common axis,

each panel being so mounted in its respective frame that it is independently adjustable and removable.

Another object of this invention is to provide a blackboard of the class aforementioned which is provided with a novelly constructed detachable bumper that is easily repaired or replaced withouty danger of injury to the panel.

Further obj ects of the present invention are simplicity and economy of construction, `ease of operation and adaptability to blackboards Aconstructed of various kinds of material. The invention is disclosed in the accompanying drawing, wherein:

Figure 1 is a side elevation of a blackboard embodying the preferred form of this invention with a portion of some of the panels partially broken away.

. Fig. 2 is an enlarged fragmentary view of a portion of the device with some of thev parts in section.

Fig. 3 is an enlarged section taken on line IIL-III of Fig. 1.

Fig. 4 is an enlarged section taken on line 4.5 IV-IV of Fig. 1, and,

Fig. 5 is a section taken on line V-V of Fig. 1.

kLike reference characters designate similar parts throughout the several views and the numeral 10 indicates a pair of similar brackets adapted to be securely attached to the wall or other suitable supporting'structure with pintles 12 carried thereby in substantially vertical axial alinement. Each bracket 10 is provided with two spaced a art lugs 14 which carry the pintles 12, on w rich the several hinge arms 16 of the frame members 18 are pivotally mounted. Each hinge arm 16 is spaced apart from the arm next thereto by means of a washer 2O which is 60 vertically slidable on the pintle, but is se? cured in any suitable manner against oscillation, thus precluding the accidental movement of any of the blackboard panels or leaves 22, which are carried by their cooperating frames 18, other than the one being oscillated. Panel 22, while preferably made of slate, may be made. of any other suitable material such as composition board, etc. The frame 18 is preferably made with a recess 24, into which one end of the panel or leaf 22 may be inserted and with the parallel walls 26 and 28 extending over a portion of the top and bottom edges respectively of the panel. The frame member 18 as shown, 75 is made of a top corner cap 8O and a bottom corner cap 82, secured together by a suitable channel member 34 which engages the edge of the panel 22. yIt is obvious that this -frame might be made of a unitary structure or the parts may be made separately and welded or otherwise secured rigidly together.

Referring to Fig. 2, it will be noted that the panel 22 is provided adjacent its top and bottom edges with recesses or notches 86, into which projections 88 and 40 respectively may be inserted to secure the panel to the frame 18. While the recesses in panel 22 are shown as notches in the edge thereof, it is also apparent that these recesses may be produced by forming a hole through the panel or by forming a recess in the face of the panel.

Projections 38 and 4:0 are positioned on caps 30 and 32 respectively with their body portion extending through openings .42 formed therethrough and with their inner portions engaging the recesses or notches 36. When the projections are thus positioned in the operative position they are secured to the frame 18 against accidental movement by screws 44.

Due to the fact that the entire weight of the panel is supported by one of its ends it is apparent that the projection 38 will be subject- 1edito considerable strain due to gravity. The

lower portion of the panel will rest against the horizontal wall 28, while the adjacent vertical portion of the panel will have a backward thrust against frame 18, thereby relieving the projection 40 of any material strain. However, projection 40 does function to prevent the raising of the panel. lt will be noted that the inner end of projection 40 is made narrower than the width of the recess 36, thereby allowing horizontal adjustment of the panel as hereinafter described. To preclude possible injury to the panel a soft buffer member 4l is positioned between the projection 38 and the panel- 22 at the point of reatest pressure.

Sgince a plurality of panels are to be hinged on a common aXis and it is desirable to have their edges parallel and in alinement, it is necessary to provide means for innependently raising and lowering the outer end of each panel. To facilitate this requirement screws 47 are mounted in threaded openings 43 formed through the vertical side of corner cap 32 and positioned in alinement with the edge of panel 22 so that as the screws are operated they will force the lower portion of panel 22 from frame 18, thus raising the outer end of the panel, and since, as stated above, the lower end of the panel exerts an inward pressure against frame 18 at all times, due to gravity, when screws 47 are retracted, the lower end of the panel will follow them inwardly thereby lowering the outer end of the panel.

With the inner ends of panels positioned in alinement on the hinge members, it is apparent that the top and bottom edges of each panel of the set may be quickly adjusted so as to properly register with the other panels of the set. In order to present a larger surface of contact for the vertical adjusting means a suitable plate 45 is positioned between screws 47 and the edge of panel 22.

To protect the outer edges of the panel 22 and preclude possible chipping thereof, a suitable channeled edging 46 is formed in a U-shape to slip over the edges of said panel and extend into cap members 30 and 32 respectively. Each end of the edging 46 is provided with an opening 48, through which projections 88 and 40, respectively,pass,there by holding the edging member and panel in fixed relative position. Referring to Fig. 5 it will be noted that the edging 46 has inturned flanges 50 which are adapted to contact the surface of the panel. This edging 46 is made of suliiciently light flexible material to allow for frictional engagement against the surfaces of panels of different thicknesses. ySlidablymounted on edging 46 the panel slid out of engagement with the frame 18, thus making it possible for one man to easily install the blackboard by first positioning the hinges and frames on the struc ture and then mounting the blackboard panels separately in their respective frames.

It is obvious that changes may be made in this device without departing from the spirit of this invention and therefore, I do not limit this invention to the precise construction shown and described.

Vhat is claimed as new is:

l. A blackboard comprising a vertically disposed panel, a frame adapted to engage one end of said panel, means carried adjacent the top of said frame for securing the panel to said frame, and means, carried by said frame, adjustable to move the lower portion of the panel toward or from said frame.

2. A blackboard comprising a vertically disposed panel, a hingedly supported frame adapted to engage one end of said panel, means carried adjacent the top of said frame for securing said panel to said frame; and means, carried by said frame, adjustable to move said panel toward or from said frame.

3. A blackboard comprising a vertically disposed panel, a frame pivotally mounted for horizontal movement adapted to encompass one end of said panel, detachable means carried by said frame to secure said panel to said frame, means carried by said frame adjustable to move the lower portion of said panel toward and from said frame, and a U- shaped channeled member encompassing the outer end of said panel.

4. A blackboard comprising a vertically,

disposed panel, a frame adapted to engage one end of said panel, a recess formed in said panel, a projection carried by the upper portion of said frame adapted to engage said recess to secure said panel to said frame, and means carried by said frame adjustable to move the lower portion of said panel from said frame.

5. A blackboard comprising a vertically disposed panel, a frame adapted to engage one end of said panel, a recess formed in said panel, a projection carried by the upper portion of said frame adapted to engage said recess to secure said panel against outward movement, and means carried by said frame, below said detent, adjustable to cause said panel to move toward or from said frame.

6. A blackboard comprising a vertically disposed panel, a frame pivotally mounted` for horizontal movement, means carried by said frame to secure said panel to said frame, a U-shaped channeled member encompassing the outer edge of said panel, a bumper slidably mounted on said channel member and means carried by the frame adjustable to raise and lower said bumper.

7. A blackboard comprising a vertically disposed panel, having recesses formed in its upper and lower portions respectively, a

frame pivotally mounted for horizontal movement, adapted to encompass one end of said panel, a detachable projection carried by said Jframe adapted to enter the recess in the upper portion of said panel to secure the panel to the frame, a detachable projection carried by the frame positioned to engage in the recess in the lower portion of said panel to allow a limited longitudinal movement of the panel, and adjustable means carried by the frame movable to cause the lower portion of the panel to move toward or from the frame.

8. A blackboard comprising a vertically disposed panel, a frame adapted to encompass one end of said panel, adjustable means carried by said frame to secure said panel to said frame, and means carried by said frame adjustable to raise or lower the panel end remote from said frame.

In testimony whereof, I hereunto ax my signature.

CHARLES H. KRAFT. 

